Thermally laminated tab liner
AssigneeTekni-Plex, Inc.
InventorPhilip D. Bourgeois
Life of this patent
Estimating the term…
Abstract
Liner having an induction heat sealable layer for sealing to a rim of a container, and a pull tab for ease of removal of the liner from the container rim. A folded insert disposed between multilayer upper and lower components, has a heat bondable polyolefin layer that is thermally laminated to polyolefin layers of the upper and lower components, forming a pull tab between the integrated polyolefin layers. The resulting composite resists delamination and can be formed in a single thermal lamination step, avoiding the multiple lamination steps, associated high equipment costs, and complex layer constructions of the prior art.
Claims26
A liner comprising:
- three stacked multilayer components thermally laminated together to form a composite liner, the liner having an induction heat sealable lower layer for sealing to a rim of a container and a pull tab for ease of removal of the liner from the rim of the container, the three multilayer components comprising:
- an upper multilayer component (UMC) comprising an upper support layer and a lower heat bondable polyolefin layer;
- and
- a lower multilayer component (LMC) comprising an upper heat bondable polyolefin layer, the lower induction heat sealable layer, and an inductive heating layer therebetween;
- a folded insert comprising upper and lower multilayer insert portions joined at a fold line, each insert portion comprising an outer heat bondable polyolefin layer and an inner heat resistant separable layer wherein in a folded position the inner separable layers of the insert portions are facing one another and resist bonding by thermal lamination and induction heating to form the pull tab in the liner,
- the liner being formed by a method comprising:
- in a first area of the liner the UMC and LMC polyolefin layers are disposed facing one another and are thermally laminated by application of heat and pressure to form an integral polyolefin layer of a non-separable first liner portion;
- and
- in a second area of the liner the polyolefin layers of the upper and lower insert portions are disposed facing the UMC and LMC polyolefin layers respectively and thermally laminated, by application of heat and pressure, to form integral polyolefin layers in a second liner portion having the pull tab.
A method of forming a liner comprising:
- thermally laminating together three stacked multi-layer components to form a composite liner, the liner having an induction heat sealable lower layer for sealing to a rim of a container and a pull tab for ease of removal of the liner from the rim of the container, the three multi-layer components comprising:
- an upper multilayer component (UMC) comprising an upper support layer and a lower heat bondable polyolefin layer;
- and
- a lower multilayer component (LMC) comprising an upper heat bondable polyolefin layer, the lower induction heat sealable layer, and an inductive heating layer therebetween;
- a folded polymer insert comprising upper and lower multilayer insert portions joined at a fold line, each insert portion comprising an outer heat bondable polyolefin layer and an inner heat resistant separable layer wherein in a folded position the inner separable layers of the two insert portions are facing one another and resist bonding by thermal lamination and induction heating to form the pull tab in the liner,
- wherein the method includes:
- disposing a first area of the UMC and LMC polyolefin layers facing one another,
- disposing the folded insert between a second area of the UMC and LMC polyolefin layers with the polyolefin layers of the upper and lower insert portions disposed facing the UMC and LMC polyolefin layers respectively, and
- forming a non-separable first liner portion by thermally laminating the facing polyolefin layers in the first area by application of heat and pressure to form an integral polyolefin layer, and
- forming a second liner portion having the pull tab by thermally laminating the facing polyolefin layers in the second area by application of heat and pressure to form integral polyolefin layers in the second liner portion.
Dependencies are inferred from the claim text.